The Effect of Levonorgestrel-releasing Intrauterine Device on Endometrial Hyperplasia

To evaluate the efficacy of the levonorgestrel releasing intrauterine device (Mirena) in the treatment of hyperplasia of the endometrium and its effects on the changes of pathological structure and ultramicrostructure of the endometrium. 25 cases of dysfunctional uterine bleeding with endometrial hyperplasia in the age of 30 to 51 years without the request of having baby were included. Levonorgestrel releasing intrauterine devices (Mirena) were inserted in the patients at the 4～7th day of menstrual cycle. There was a more than 2/3 reduction in menstrual blood loss in 3 months and 6 months after the insertion, the PBAC score was reduced significantly (P0.01). Hemoglobin level was returned to normal at 6 months after the insertion (P0.05). Endometrial thickness measured by ultrasonography reduced significantly from (8.5±3.5) mm to (3.5±1.5) mm (P0.05). Pathological examinations performed 3～12 months after the insertion demonstrated endometrial hyperplasia had been reversed in all cases. The endometrium exhibited visible secretion and a pseudo decidual reaction. The electron microscopy demonstrated the presence of solidified endometrial epithelia, the loss of cellular prominency and microvilli, enlargement of gap junction, and the shedding epithelia. Euchromatin in nuclei concreted as a small mass and accumulated around the membrane. The membrane of the nuclei was irregular and depressed. Distended endoplasmic reticulum swelling mitochondria have been found morphologically. Changes could be concluded as cell denaturalization and inhibition of proliferation. [Conclusion] Levonorgestrel releasing intrauterine device is an effective non operative therapy in endometrial hyperplasia. It can not only significantly reduce the menstrual blood loss but also reverse the endometrial hyperplasia effectively.